1. Field of the Invention
This invention relates to a modular spacecraft system formed by connecting substantially identical spacecraft modules, and to the construction of the individual spacecraft modules used to assemble the modular spacecraft system. The invention further relates to a method for deployment of the spacecraft modules and to a method for assembly of the modular spacecraft system.
2. Description of the Prior Art
Prior to the present invention, the concept of modular spacecraft design was limited to the combination of a number of modules having different functions to form a fully operable spacecraft. For example, a specific module might contain equipment, such as solar collection devices, antennas and other communications equipment, or other hardware and subsystems required for operation of the spacecraft, such as attitude and orbit control devices or tracking, telemetry and command equipment.
A number of modular space station designs have also been proposed in which several cylindrically-shaped modules are connected to and communicate with a central corridor or core module or modules. Solar collection devices are located at various positions on the space station. The major drawback to these proposed modular space stations is that none of the modules which are connected to the control modules can operate independently. Several modules must be connected together before the space station can be operational. Thus, modules can only be connected to the space station which can be supported by the existing structure. Another drawback is that the effort and cost of design and development of one of the various modules used to construct the space station cannot benefit significantly from the design and development of another module of different design and function. Thus, the fact that each module is of different design and cannot operate independently substantially increases the total cost and effort of design and development of the space station.
Methods suggested for construction of these proposed modular space stations have involved placing of the construction capability on the orbiting part of the station. For example, it has been suggested that a remote manipulator system (RMS), which is movable along a track, be placed on the central corridor or core module. When approached by an oribiting National Space Transportation System (NSTS), also referred to as the Space Shuttle, equipped with its own RMS and carrying an additional module for the space station, the RMS on the core module would attach to the Shuttle and bring it closer to the core module. The core module RMS would then attach to the additional module or other equipment in the Shuttle cargo bay, remove it from the cargo bay and place it in the appropriate position on the space station. Alternatively, the Shuttle RMS would attach to the additional module or other equipment in the Shuttle cargo bay and hand it to the core module RMS which would then place it in the appropriate position on the space station. All of these suggestions, however, require that elaborate construction capability be developed for use on the orbiting space station. Other suggested methods have employed free-flying vehicles to ferry modules between the Shuttle and the space station being constructed.